Update to latest Go weekly.

ftp.go

@@ -5,10 +5,10 @@ import (
 	"io"
 	"net"
 	"net/textproto"
-	"os"
 	"fmt"
 	"strconv"
 	"strings"
+	"errors"
 )
 
 type EntryType int
@@ -36,7 +36,7 @@ type response struct {
 }
 
 // Connect to a ftp server and returns a ServerConn handler.
-func Connect(addr string) (*ServerConn, os.Error) {
+func Connect(addr string) (*ServerConn, error) {
 	conn, err := textproto.Dial("tcp", addr)
 	if err != nil {
 		return nil, err
@@ -54,7 +54,7 @@ func Connect(addr string) (*ServerConn, os.Error) {
 	return c, nil
 }
 
-func (c *ServerConn) Login(user, password string) os.Error {
+func (c *ServerConn) Login(user, password string) error {
 	_, _, err := c.cmd(StatusUserOK, "USER %s", user)
 	if err != nil {
 		return err
@@ -65,7 +65,7 @@ func (c *ServerConn) Login(user, password string) os.Error {
 }
 
 // Enter extended passive mode
-func (c *ServerConn) epsv() (port int, err os.Error) {
+func (c *ServerConn) epsv() (port int, err error) {
 	c.conn.Cmd("EPSV")
 	_, line, err := c.conn.ReadCodeLine(StatusExtendedPassiveMode)
 	if err != nil {
@@ -74,7 +74,7 @@ func (c *ServerConn) epsv() (port int, err os.Error) {
 	start := strings.Index(line, "|||")
 	end := strings.LastIndex(line, "|")
 	if start == -1 || end == -1 {
-		err = os.NewError("Invalid EPSV response format")
+		err = errors.New("Invalid EPSV response format")
 		return
 	}
 	port, err = strconv.Atoi(line[start+3 : end])
@@ -82,7 +82,7 @@ func (c *ServerConn) epsv() (port int, err os.Error) {
 }
 
 // Open a new data connection using extended passive mode
-func (c *ServerConn) openDataConn() (net.Conn, os.Error) {
+func (c *ServerConn) openDataConn() (net.Conn, error) {
 	port, err := c.epsv()
 	if err != nil {
 		return nil, err
@@ -100,7 +100,7 @@ func (c *ServerConn) openDataConn() (net.Conn, os.Error) {
 }
 
 // Helper function to execute a command and check for the expected code
-func (c *ServerConn) cmd(expected int, format string, args ...interface{}) (int, string, os.Error) {
+func (c *ServerConn) cmd(expected int, format string, args ...interface{}) (int, string, error) {
 	_, err := c.conn.Cmd(format, args...)
 	if err != nil {
 		return 0, "", err
@@ -111,7 +111,7 @@ func (c *ServerConn) cmd(expected int, format string, args ...interface{}) (int,
 }
 
 // Helper function to execute commands which require a data connection
-func (c *ServerConn) cmdDataConn(format string, args ...interface{}) (net.Conn, os.Error) {
+func (c *ServerConn) cmdDataConn(format string, args ...interface{}) (net.Conn, error) {
 	conn, err := c.openDataConn()
 	if err != nil {
 		return nil, err
@@ -136,10 +136,10 @@ func (c *ServerConn) cmdDataConn(format string, args ...interface{}) (net.Conn,
 	return conn, nil
 }
 
-func parseListLine(line string) (*Entry, os.Error) {
+func parseListLine(line string) (*Entry, error) {
 	fields := strings.Fields(line)
 	if len(fields) < 9 {
-		return nil, os.NewError("Unsupported LIST line")
+		return nil, errors.New("Unsupported LIST line")
 	}
 
 	e := &Entry{}
@@ -151,14 +151,14 @@ func parseListLine(line string) (*Entry, os.Error) {
 	case 'l':
 		e.Type = EntryTypeLink
 	default:
-		return nil, os.NewError("Unknown entry type")
+		return nil, errors.New("Unknown entry type")
 	}
 
 	e.Name = strings.Join(fields[8:], " ")
 	return e, nil
 }
 
-func (c *ServerConn) List(path string) (entries []*Entry, err os.Error) {
+func (c *ServerConn) List(path string) (entries []*Entry, err error) {
 	conn, err := c.cmdDataConn("LIST %s", path)
 	if err != nil {
 		return
@@ -170,7 +170,7 @@ func (c *ServerConn) List(path string) (entries []*Entry, err os.Error) {
 	bio := bufio.NewReader(r)
 	for {
 		line, e := bio.ReadString('\n')
-		if e == os.EOF {
+		if e == io.EOF {
 			break
 		} else if e != nil {
 			return nil, e
@@ -183,17 +183,21 @@ func (c *ServerConn) List(path string) (entries []*Entry, err os.Error) {
 	return
 }
 
-func (c *ServerConn) ChangeDir(path string) os.Error {
+// Changes the current directory to the specified path.
+func (c *ServerConn) ChangeDir(path string) error {
 	_, _, err := c.cmd(StatusRequestedFileActionOK, "CWD %s", path)
 	return err
 }
 
-func (c *ServerConn) ChangeDirToParent() os.Error {
+// Changes the current directory to the parent directory.
+// ChangeDir("..")
+func (c *ServerConn) ChangeDirToParent() error {
 	_, _, err := c.cmd(StatusRequestedFileActionOK, "CDUP")
 	return err
 }
 
-func (c *ServerConn) CurrentDir() (string, os.Error) {
+// Returns the path of the current directory.
+func (c *ServerConn) CurrentDir() (string, error) {
 	_, msg, err := c.cmd(StatusPathCreated, "PWD")
 	if err != nil {
 		return "", err
@@ -203,14 +207,15 @@ func (c *ServerConn) CurrentDir() (string, os.Error) {
 	end := strings.LastIndex(msg, "\"")
 
 	if start == -1 || end == -1 {
-		return "", os.NewError("Unsuported PWD response format")
+		return "", errors.New("Unsuported PWD response format")
 	}
 
-	return msg[start+1:end], nil
+	return msg[start+1 : end], nil
 }
 
-// Retrieves a remote file
-func (c *ServerConn) Retr(path string) (io.ReadCloser, os.Error) {
+// Retrieves a file from the remote FTP server.
+// The ReadCloser must be closed at the end of the operation.
+func (c *ServerConn) Retr(path string) (io.ReadCloser, error) {
 	conn, err := c.cmdDataConn("RETR %s", path)
 	if err != nil {
 		return nil, err
@@ -220,8 +225,10 @@ func (c *ServerConn) Retr(path string) (io.ReadCloser, os.Error) {
 	return r, nil
 }
 
-func (c *ServerConn) Stor(name string, r io.Reader) os.Error {
-	conn, err := c.cmdDataConn("STOR %s", name)
+// Uploads a file to the remote FTP server.
+// This function gets the data from the io.Reader. Hint: io.Pipe()
+func (c *ServerConn) Stor(path string, r io.Reader) error {
+	conn, err := c.cmdDataConn("STOR %s", path)
 	if err != nil {
 		return err
 	}
@@ -236,7 +243,8 @@ func (c *ServerConn) Stor(name string, r io.Reader) os.Error {
 	return err
 }
 
-func (c *ServerConn) Rename(from, to string) os.Error {
+// Renames a file on the remote FTP server.
+func (c *ServerConn) Rename(from, to string) error {
 	_, _, err := c.cmd(StatusRequestFilePending, "RNFR %s", from)
 	if err != nil {
 		return err
@@ -246,35 +254,41 @@ func (c *ServerConn) Rename(from, to string) os.Error {
 	return err
 }
 
-func (c *ServerConn) Delete(name string) os.Error {
-	_, _, err := c.cmd(StatusRequestedFileActionOK, "DELE %s", name)
+// Deletes a file on the remote FTP server.
+func (c *ServerConn) Delete(path string) error {
+	_, _, err := c.cmd(StatusRequestedFileActionOK, "DELE %s", path)
 	return err
 }
 
-func (c *ServerConn) MakeDir(name string) os.Error {
-	_, _, err := c.cmd(StatusPathCreated, "MKD %s", name)
+// Creates a new directory on the remote FTP server.
+func (c *ServerConn) MakeDir(path string) error {
+	_, _, err := c.cmd(StatusPathCreated, "MKD %s", path)
 	return err
 }
 
-func (c *ServerConn) RemoveDir(name string) os.Error {
-	_, _, err := c.cmd(StatusRequestedFileActionOK, "RMD %s", name)
+// Removes a directory from the remote FTP server.
+func (c *ServerConn) RemoveDir(path string) error {
+	_, _, err := c.cmd(StatusRequestedFileActionOK, "RMD %s", path)
 	return err
 }
 
 // Sends a NOOP command. Usualy used to prevent timeouts.
-func (c *ServerConn) NoOp() os.Error {
+func (c *ServerConn) NoOp() error {
 	_, _, err := c.cmd(StatusCommandOK, "NOOP")
 	return err
 }
 
-func (c *ServerConn) Quit() os.Error {
+// Properly close the connection from the remote FTP server.
+// It notifies the remote server that we are about to close the connection,
+// then it really closes it.
+func (c *ServerConn) Quit() error {
 	c.conn.Cmd("QUIT")
 	return c.conn.Close()
 }
 
-func (r *response) Read(buf []byte) (int, os.Error) {
+func (r *response) Read(buf []byte) (int, error) {
 	n, err := r.conn.Read(buf)
-	if err == os.EOF {
+	if err == io.EOF {
 		_, _, err2 := r.c.conn.ReadCodeLine(StatusClosingDataConnection)
 		if err2 != nil {
 			err = err2
@@ -283,6 +297,6 @@ func (r *response) Read(buf []byte) (int, os.Error) {
 	return n, err
 }
 
-func (r *response) Close() os.Error {
+func (r *response) Close() error {
 	return r.conn.Close()
 }